Engaging/disengaging fail-safe door closing device for rolling fire door and door machine having same

Abstract

There is disclosed an engaging/disengaging fail-safe door closing device for a rolling fire door, provided between a power device and a speed reducing device of a door machine, including an electromagnet fixed inside a housing of the door machine and disposed around the outside of a shaft of the power device; a brake device including a shaft sleeve, loosely embracing around the outside of the shaft of the power device and being capable of sliding between the shaft and the electromagnet, on one end of which, there is provided an attracted plate facing the magnet and coming off the magnet by way of the biasing force of an elastic element, while on the other end there is radially formed a brake disk; a driving plate fixed on the shaft of the power device and facing a position where the brake disk is allowed to contact; and a circuit used to control the electromagnet to be electrified to excite in order for actuating the brake when the door reaches a predetermined position, or to release the brake when the power is cut off.

1. An engaging/disengaging fail-safe door closing device for a rolling fire door, provided between a power means ( 10 ) and a speed reducing means ( 50 ) of a door machine ( 1 ), used to close said rolling fire door immediately in a condition of power failure, comprising:
 an electromagnet means ( 30 ) fixed inside a housing ( 2 ) of said door machine ( 1 ) and disposed around the outside of a shaft ( 11 ) of said power means ( 10 ); 
 a brake means ( 40 ) including a shaft sleeve ( 41 ), loosely embracing around the outside of said shaft ( 11 ) of said power means ( 10 ) and being capable of sliding between said shaft and said electromagnet means ( 30 ), on one end of said shaft sleeve ( 41 ) there is provided an attracted plate ( 43 ) facing said magnet means ( 30 ) and coming off said magnet means ( 30 ) by way of the biasing force of an elastic element ( 35 ), while on the other end of said shaft sleeve ( 41 ) there is radially formed a brake disk ( 44 ); 
 a driving plate ( 12 ) fixed on said shaft ( 11 ) of said power means ( 10 ) and facing a position where said brake disk ( 44 ) is allowed to contact; and 
 a circuit ( 53 ) used to control said power means ( 10 ) so as to actuate the brake when said power means ( 10 ) is switched on and said electromagnet means ( 30 ) is disconnected or release the brake when said power means ( 10 ) is disconnected and said electromagnetic means ( 30 ) is switched on. 
 
     
     
       2. The engaging/disengaging fail-safe door closing device for rolling fire door according to  claim 1 , wherein an accommodation room ( 3 ) is defined by said housing ( 2 ) between said power means ( 10 ) and said speed reducing means ( 50 ) of said door machine ( 1 ), said accommodation room ( 3 ) being formed therein with a radial partition ( 4 ) dividing it into a first accommodation room ( 3   a ) and a second accommodation room ( 3   b ), said partition ( 4 ) extending toward said first accommodation room ( 3   a ) and provided at the center thereof with a bearing part ( 5 ) supporting around the outside of said shaft sleeve ( 41 ). 
     
     
       3. The engaging/disengaging fail-safe door closing device for rolling fire door according to  claim 2 , wherein said electromagnet means ( 30 ) is accommodated within said first accommodation room ( 3   a ) and fixed on said partition ( 4 ), in which a hollow aperture ( 31 ) is provided at the center of said electromagnet means and embracingly provided around the outside of said bearing part ( 5 ), as well as an accommodation space ( 32 ) between said hollow aperture ( 31 ) and said bearing part ( 5 ). 
     
     
       4. The engaging/disengaging fail-safe door closing device for rolling fire door according to  claim 3 , wherein said elastic element ( 35 ) is accommodated within said accommodation space ( 32 ), and comprises two ends, one of which is rested against said partition ( 4 ), while the other is pressed against said attracted plate ( 43 ). 
     
     
       5. The engaging/disengaging fail-safe door closing device for rolling fire door according to  claim 2 , wherein said brake disk ( 44 ) of said brake means ( 40 ) is accommodated within said second accommodation room ( 3   b ), and limited by a plurality of locating pins ( 45 ) to axially slide over said partition ( 4 ) only. 
     
     
       6. The engaging/disengaging fail-safe door closing device for rolling fire door according to  claim 1 , wherein a centrifugal type stalling protective device ( 20 ) is further included between said power means ( 10 ) and said speed reducing means ( 50 ) of said door machine ( 1 ) and provided at the center thereof with an axially extending shaft sleeve ( 21 ). 
     
     
       7. The engaging/disengaging fail-safe door closing device for rolling fire door according to  claim 6 , wherein said shaft ( 11 ) of said power means ( 10 ) comprises a first shaft ( 11   a ) and a second shaft ( 11   b ) coupled as a unit by means of said shaft sleeve ( 21 ). 
     
     
       8. The engaging/disengaging fail-safe safe door closing device for rolling fire door according to  claim 1 , wherein a plurality of brake linings ( 46 ) are provided on one end surface of said brake disk ( 44 ) facing said driving plate ( 12 ). 
     
     
       9. A door machine ( 1 ), comprising:
 a housing ( 2 ) enclosing an accommodation room ( 3 ) having two opening ends, said accommodation room ( 3 ) being formed therein with a radial partition ( 4 ), which divides said accommodation room into a first accommodation room ( 3   a ) and a second accommodation room ( 3   b ), and provided with a bearing part ( 5 ) extending toward said first accommodation room ( 3   a ) at the center of said partition ( 4 ); 
 a power means ( 10 ) coupled to one of said opening ends of said housing ( 2 ) and provided with a shaft ( 11 ) passing through the center of said bearing part ( 5 ) and extending toward the other opening end; 
 a speed reducing means ( 50 ) connected to said the other opening end of said housing ( 2 ) and used to transmit power from said shaft ( 11 ) to an output shaft ( 52 ) by means of a plurality of gear sets ( 51 ); 
 an electromagnet means ( 30 ), composed of a winding ( 33 ) and a magnet core ( 34 ), being accommodated within said first accommodation room ( 3   a ) and fixed on said partition ( 4 ), a hollow aperture ( 31 ) at the center of said magnet core ( 34 ) being embracingly provided around the outside of said bearing part ( 5 ), and an accommodation space ( 32 ) remaining between said hollow aperture and said bearing part ( 5 ); 
 a brake means ( 40 ) including a shaft sleeve ( 41 ) loosely embracing around the outside of said shaft ( 11 ) and axially sliding between said shaft and said bearing part ( 5 ), on one end of said shaft sleeve, there being fixed with an attracted plate ( 43 ) located within said first accommodation room ( 3   a ) and facing said magnet core ( 34 ); while on the other end thereof, there being radially formed with a brake disk ( 44 ) located within said second accommodation room ( 3   b ), as well as a plurality of locating pins ( 45 ) fixed on said partition ( 4 ) being used to limit said brake disk ( 44 ) to axially slide only, and a plurality of brake linings ( 46 ) being provided on one end surface of said brake disk ( 44 ) facing outward; 
 an elastic element ( 35 ) accommodated within said accommodation space ( 32 ) and having two ends, one of which is rested against said partition ( 4 ), while the other is pressed against said attracted plate ( 43 ); 
 a driving plate ( 12 ) located within said second accommodation room ( 3   b ) and fixed at the center thereof on said shaft ( 11 ), while facing a position where said brake plate ( 44 ) and said brake lining ( 46 ) are allowed to contact; and 
 a circuit used to control said door machine ( 1 ), such that said winding ( 33 ) of said electromagnet means ( 30 ) is electrified to excite in order for actuating the brake when said door is opened to a predetermined location, or that the brake is released when the power is cut off. 
 
     
     
       10. The door machine according to  claim 9 , wherein between said power means ( 10 ) and said speed reducing means ( 50 ), there is further included a centrifugal type stalling protective device ( 20 ) having an axially extending shaft sleeve ( 21 ) at the center thereof. 
     
     
       11. The door machine according to  claim 10 , wherein said shaft ( 11 ) of said power means ( 10 ) comprises a first shaft ( 11   a ) and a second shaft ( 11   b ) coupled as a unit by means of said shaft sleeve ( 21 ).